Fiber application head comprising heating means associated with functional modules

ABSTRACT

A fiber application head comprising a compaction system including a plurality of independent compaction rollers and compaction cylinders and, for each fiber, cutting means and rerouting means. For each fiber, the head comprises a functional module including the cutting means and the rerouting means, each functional module is mounted so as to be movable in translation on a support element of the head. Each compaction roller is mounted on one or more adjacent functional modules. A compaction cylinder is associated with the functional module(s) associated with a compaction roller for the displacement in translation of the functional module(s). An independent heating system is associated with each compaction roller, and able to displace with the functional module(s) associated with a compaction roller.

RELATED CASES

The present application is a National Phase entry of PCT Application No.PCT/FR2019/000060, filed Apr. 23, 2019 which claims priority from FRPatent Application No. 18/00446, filed Apr. 25, 2018, which applicationsare hereby incorporated by reference in their entireties.

TECHNICAL FIELD

The present invention relates to a fiber application head for theproduction of composite material parts, and more particularly a fiberapplication head comprising particular heating means associated withfunctional modules. The present invention also relates to a method forthe manufacture of composite material parts by means of a correspondingapplication head.

BACKGROUND ART

Fiber application machines are known for the application by contact on alay-up tool, such as a male or female mold, of a wide band formed of oneor more tow type continuous flat fibers, dry or impregnated withthermosetting or thermoplastic resin, in particular carbon fibers,consisting of a multitude of carbon threads or filaments.

These fiber application machines, also called fiber placement machines,typically include an application head, a displacement system able todisplace the application head, and storage means to store the fibers.The fiber storage means can be mounted on the head, or can be located ata distance from the head. The head conventionally comprises a compactionsystem including at least one application roller for the application ofa band formed of several fibers arranged edge to edge onto anapplication surface of a lay-up tool, a guiding system for guiding thefibers in the form of a band towards the application roller, and foreach fiber, cutting means for cutting a fiber, rerouting means forrerouting the fiber to the application roller after a cut performed bythe cutting means, and clamping means for clamping the fiber that hasjust been cut.

The compaction system further includes at least one compaction cylinderfor applying the fiber with a compaction force.

In order to be able to apply wide fiber bands, especially on concave orconvex application surfaces, it has been proposed notably in the patentdocument EP2594389, to use a compaction system comprising independentcompaction rollers. Each roller is used to apply a single fiber, and issupported by a fastening system comprising a motor-driven heightdisplacement system and a compaction cylinder to compensate forirregularities in the application surface. Such a compaction system, aswell as the cutting means and the rerouting means for each fiber can bedifficult to control, especially to achieve lay-up accuracies in thecase of cutting and rerouting fibers on the fly.

The rollers are arranged in staggered rows in two parallel rows to beable to apply fiber bands in which the fibers are tangent to each otherlaterally. Such positioning of the rollers in two rows simplifies thearchitecture of the head, and in particular the mounting of thedifferent rollers on the head.

In the case of lay-up of fibers pre-impregnated with a thermosettingpolymer, it can be envisaged to provide the head with heating meansarranged upstream of the compaction rollers, for example in the form oframps of infrared lamps, to heat the application surface or the fiberspreviously laid-up and thus ensure the adhesion of the various plies toeach other during lay-up.

For certain types of fibers, such as dry fibers provided with a binder,or fibers pre-impregnated with a thermoplastic polymer, it is necessaryto heat the lay-up surface, as well as the fibers to be laid-up,preferably at the contact area between the roller and the surface. Thehead proposed in the cited patent document makes difficult, evenimpossible the lay-up of such fibers.

The purpose of the present invention is to propose a solution toovercome at least one of the above-mentioned drawbacks.

SUMMARY

For this purpose, the embodiments of the present invention proposes afiber application head for the production of composite material parts byapplication of bands formed of several continuous fibers arranged sideby side, preferably edge to edge, comprising a compaction systemcomprising several independent compaction rollers and compactioncylinders for applying the fibers with a compaction force and, for eachfiber, cutting means and rerouting means, and preferably clamping means,characterized in that

-   -   for each fiber, the head comprises a functional module including        the cutting means and the rerouting means, each functional        module is mounted so as to be movable in translation along a        compaction direction on a support element of the head,    -   each compaction roller is mounted on one or more adjacent        functional modules;    -   a compaction cylinder is associated with the functional        module(s) associated with a compaction roller for the        displacement in translation of the functional module(s),    -   the head further comprising heating means, arranged upstream of        the compaction rollers with respect to the advancement direction        of the head during lay-up, comprising an independent heating        system associated with each compaction roller, the heating        system being able to displace with the functional module(s)        associated with the one compaction roller, when the functional        module(s) displace along the compaction direction.

According to embodiments of the invention, a heating system isassociated with each compaction roller and displaces in the compactiondirection with the associated functional module(s), ensuring optimumheating during lay-up. The heating system is adjusted so that it is ableto emit heat radiation towards the lay-up surface and/or one or morepreviously applied fibers, preferably in the direction of the nip orcontact area between the compaction roller and the application surface,in order to heat the fiber located on the roller, before its compactionby the latter, as well as the application surface and/or one or morepreviously applied fibers. When the functional module is displaced inthe compaction direction, the distance between the heating system andthe application surface, the distance between the heating system and thecompaction roller, and the orientation of the radiation with respect tothe application surface and the compaction roller vary slightly,preferably remain substantially constant.

According to an embodiment, characterized in that the heating system isable to emit a thermal radiation towards the nip or contact area betweenthe compaction roller and the application surface, in order to heat eachfiber located on the compaction roller, prior to its compaction by thelatter, as well as the application surface and/or one or more previouslyapplied fibers.

According to an embodiment, each heating system includes one or more hotair torches, a laser type heating system, or a flash lamp type heatingsystem.

According to an embodiment, the heating system is mounted directly onthe module(s) associated with a same compaction roller.

According to another embodiment, each heating system is mounted so as tobe movable in translation in the compaction direction on the supportelement, upstream of the functional module(s) associated with a samecompaction roller, and is mechanically connected by at least one rigidarm to the functional module(s). In this embodiment mode, thedisplacement of the heating system is ensured by the compaction cylindervia the connecting arm. In one embodiment variant, the heating system isdisplaced by its own actuating system, for example a cylinder, whichoperates in synchronism with the compaction cylinder.

In another embodiment, each heating system is pivotably mounted on thesupport element, upstream of the functional module(s) associated with asame compaction roller, about an axis parallel to the rotation axis ofthe compaction rollers and is mechanically connected by at least oneconnecting rod to the functional module(s), the connecting rod beingpivotably mounted by its ends to the heating system and to thefunctional module(s).

According to an embodiment the head includes one compaction roller perfunctional module.

According to an embodiment, the head comprises at least one firstfunctional module, also called downstream functional module, and atleast one second functional module, also called upstream functionalmodule, arranged alternately side by side, each first functional modulecomprising guiding means able to guide a first fiber towards acompaction roller along a first guiding plane, and each secondfunctional module comprising guiding means able to guide a second fibretowards a compaction roller along a second guiding plane, different fromthe first guiding plane, so as to form at the compaction rollers a fiberband formed of first and second fiber(s) arranged alternately edge toedge.

The use of first and second functional module(s) guiding the fibersalong a first guide plane and a second guide plane makes it possible tolay up fiber bands in which the fibers are arranged edge to edge, thefibers being substantially adjoined by their longitudinal edges.

The head can comprise only one first functional module and only onesecond functional module, the head then being able to lay up a fiberband formed of a first fiber and a second fiber arranged edge to edge.When the head comprises several first functional modules and secondfunctional modules, the first functional modules and second functionalmodules are arranged alternately side by side, the head being able tolay up a fiber band formed of first fibers and second fibers arrangedalternately edge to edge

According to an embodiment, the compaction rollers are arranged in asingle row, side by side, preferably without contact with each other,the rotation axis of the compaction rollers being arranged in the sameplane, called the compaction plane, parallel to the compactiondirection,

This single-row arrangement allows the use of simple and efficientheating means that can heat up at the contact line between theapplication surface and each compaction roller. Surprisingly, theinventors found that partial compaction of the fibers or of certainfibers over only part of their width resulted in a satisfactory lay-upquality, and that it is therefore possible to use, in the case of a headcomprising one compaction roller per fiber, a compaction roller with awidth smaller than the width of the fiber. The compaction cylinders areable to displace the functional modules between a first extremeposition, called high position, and a second extreme position, calledlow position. The rotation axis of the rollers in the extreme highposition or in the extreme low position are substantially aligned.

The compaction rollers are aligned while being spaced apart from eachother, so that they can displace in the compaction plane independentlyof each other.

The head according to an embodiment of the invention comprises at leasttwo compaction rollers, each compaction roller being associated with onefunctional module or two functional modules.

According to an embodiment, each compaction roller is mounted on one ormore functional modules between two flanges, preferably with a clearancebetween the flanges of two adjacent compaction rollers. In anotherembodiment, each compaction roller comprises two compaction rolls,rotatably mounted in cantilevered manner on either side of the sameflange or support.

According to an embodiment, each first functional module comprisingguiding means able to guide a first fiber towards the compaction rollerassociated with the first functional module along a first guiding planeforming a first non-zero angle with the compaction plane of the rotationaxis of the compaction rollers, each second functional module comprisingguiding means able to guide a second fiber towards the compaction rollerassociated with the second functional module along a second guidingplane forming a second non-zero angle with the compaction plane of therotation axis of the compaction rollers, the second angle being greaterthan the first angle, the guiding planes being arranged on the same sideof the compaction plane.

This particular head architecture with two guide planes arranged on thesame side with respect to the compaction plane ensures optimal guidanceof the fibers as close as possible to the compaction rollers, and anangle of arrival of the fibers on the compaction rollers allowing anoptimal heating of the fibers by heating means arranged upstream of thecompaction rollers.

According to an embodiment, each support element is mounted so as to bemovable in translation on a frame of the head in a directionperpendicular to the compaction direction, so that each support elementcan be displaced from a lay-up position, in which the functional modulesare side by side and in which the head is able to lay up a fiber bandformed of fibers arranged edge to edge, to a maintenance position inwhich the functional module(s) carried by the support element is (are)spaced apart from the other support elements and accessible for carryingout maintenance operations. This mounting of the functional modules onsupport elements which are movable in translation on a frame allowssimple access to the functional modules for maintenance operations, inparticular maintenance operations on the cutting means and/or thererouting means, as well as the positioning of the fiber in eachfunctional module.

According to an embodiment, each support element carries two adjacentmodules, each functional module being preferably accessible from alateral face of the support element.

According to an embodiment, at least one support element can bedisplaced by a drive motor, the support element being for exampleequipped with a motor cooperating with a gear rack attached to theframe, the support elements being equipped with assembly means forassembling and disassembling two by two adjacent support elements.Preferably, each outer support element is able to be displaced by adrive motor.

According to an embodiment, each support element is able to carry afiber spool or fiber reel associated with each functional module carriedby the support element. According to an embodiment, the support elementcomprises a mandrel for receiving each fiber spool or reel, the axiallocking of spools or reels on their respective mandrels being carriedout by an adjacent support element when the support elements are in thelay-up position.

According to an embodiment, the application head comprises limitingmeans, preferably mechanical, able to limit the relative strokes of twoadjacent functional modules in the compaction direction, so as to allowan arrangement of the cutting means of the functional modules and aguiding of the fibers as close as possible to the compaction rollers,and thus guarantee a good lay-up quality, while avoiding collisions, inparticular between the cutting means. The limiting means comprise, forexample, for each pair of adjacent modules associated with differentcompaction rollers, a finger attached to one of the two functionalmodules and positioned between two stops of the other functional module,the two stops being spaced apart in the compaction direction.

The present invention also relates to a method for the manufacture of acomposite material part comprising the application of continuous fiberson an application surface, characterized in that the application offibers is carried out by means of a fiber application head as describedabove, by relative displacement of the application head with respect tothe lay-up surface along lay-up trajectories.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood, and other purposes, details,characteristics and advantages will appear more clearly in the followingdetailed explanatory description of a particular currently preferredembodiment of the invention, with reference to the attached schematicdrawings, on which:

FIGS. 1 and 2 are two schematic views in perspective of a fiberapplication head according to an embodiment of the invention;

FIG. 3 is a side view of the head of FIG. 1;

FIG. 4 is a schematic perspective view of a support element of the headof FIG. 1, the support element carrying two functional modules and theassociated fiber reels;

FIGS. 5 and 6 are side views of the support element of FIG. 4,illustrating respectively a downstream functional module and an upstreamfunctional module, the functional modules being in the extreme highposition;

FIGS. 7 and 8 are views similar to FIGS. 5 and 6, with the downstreamfunctional module in low position and the upstream functional module inhigh position;

FIGS. 9 and 10 are enlarged side views of the downstream and upstreamfunctional modules respectively, schematically illustrating the cuttingmeans, rerouting means and clamping means of the functional modules;

FIG. 11 is a view illustrating the relative position of the functionalmodules in FIGS. 9 and 10;

FIGS. 12, 13 and 14 are views similar to those in FIGS. 4, 5 and 7,respectively, on which heating systems of the head have been added;

FIGS. 15 and 16 are respectively perspective and side views of the headin FIG. 1, with the support elements in a maintenance position;

FIGS. 17 and 18 are similar views to FIG. 16 illustrating othermaintenance positions of the support elements; and,

FIG. 19 is a side view of a head according to an embodiment variant, andFIG. 20 is an enlarged view of detail D of FIG. 19.

DETAILED DESCRIPTION

FIGS. 1 to 3 illustrate a fiber application head according to anembodiment of the invention for the lay-up of a band formed of severalcontinuous fibers.

The head according to an embodiment of the invention is intended to beassembled to a displacement system for carrying out the fiber lay-upoperations, the fibers being in the present embodiment packaged in theform of reels, and the reels are embedded on the head.

The head comprises a support structure or frame 1 having an upper mainface 11 provided with assembly means (not shown) for assembling the headaccording to an assembly axis A, to a head displacement system, forexample the wrist of a polyarticulated robot or a gantry-type Cartesiandisplacement system.

The head carries a plurality of functional modules 2 a, 2 b arrangedside by side. Each functional module is associated with a fiber reel 91a, 91 b and includes cutting means, rerouting means and clamping means.Each module carries a compaction roller 3 a, 3 b.

The head comprises two types of functional modules, first functionalmodules 2 a, also called upstream functional modules, associated withupstream fiber reels 91 a, arranged upstream of the functional moduleswith respect to the advancement direction D (FIG. 3) of the head duringlay-up, and second functional modules 2 b, also called downstreamfunctional modules, associated with downstream fiber reels 91 b,arranged downstream of the functional modules with respect to theadvancement direction D. The functional modules are arranged in a row,the row comprising an alternating sequence of upstream functionalmodules 2 a and downstream functional modules 2 b.

The mounting of the functional modules on the frame is carried out bymeans of support elements 4, each support element, formed of one or moreparts, carrying a downstream functional module 2 a and an upstreamfunctional module 2 b.

In the present embodiment, the head is intended for the lay-up of a bandof eight fibers, the head comprises four identical support elements 4,each carrying two functional modules, the support elements beingindividually referenced under the references 4 a, 4 b, 4 c and 4 d inthe figures.

Each support element 4 is mounted on the lower main face 12 of frame 1so as to be movable in translation, in a direction T1, perpendicular tothe assembly axis A. For this mounting in translation, each supportelement 4 is equipped on an upper edge with two carriages 41 formounting the support element on two corresponding rails 13, mounted onthe bottom face 12 of the frame, extending from a first end 14 to asecond end 15 of the frame.

Referring to FIGS. 4 to 6, the support element 4 carries a downstreamfunctional module 2 a, accessible from a first lateral face 40 a of thesupport element, and an upstream functional module 2 b, accessible froma second lateral face 40 b.

The downstream functional module 2 a is mounted on the support element,movable in translation in a direction T2, which is parallel to theassembly axis A. For this mounting, the downstream functional module isequipped with carriages 21 mounted sliding on a rail 42 a, which isattached to the support element. The module is assembled at its upperpart to the end of the rod of a compaction cylinder 5 a, the cylinderbeing assembled by its body to the support element. The downstreamfunctional module carries a compaction roller 3 a at its bottom part.The compaction roller is mounted between two flanges 22 a of thedownstream functional module, movable in rotation about a rotation axisB1, which is perpendicular to the direction T2. During the displacementof the functional module in translation in the T2 direction, therotation axis B1 of the compaction roller displaces in a plane C, calledcompaction plane, which is parallel to the direction T2. The downstreamfunctional module includes fiber guiding means for guiding the fiberentering the module towards the compaction roller along a plane P1, theplane forming an angle α₁ with the plane C.

Referring to FIG. 9, the downstream functional module includes cuttingmeans 23 for cutting the fiber, rerouting means 24, for rerouting thefiber to the compaction roller after a cutting operation, and clampingmeans for clamping the fiber just cut.

The cutting means, known per se, comprise at least one blade able to bemaneuvered by a cutting cylinder between a rest position and an activeposition to cut a fiber. The clamping means, known per se, include forexample a clamping block able to be maneuvered by a clamping cylinderbetween a rest position and an active position to clamp the fiber. As anexample, the downstream functional module includes cutting means andclamping means, as described in patent document EP2134532, WO2017/072421or FR17/01245 and FR17/01247.

The rerouting means comprise a motorized drive roller 241 and acounter-roller 242 actuated by a rerouting cylinder between a restposition and an active position. The drive roller 241 is driven inrotation by a motor 243 embedded in the downstream functional module,for example by means of a belt or gear system. In active position, thecounter-roller is able to press the fiber against the drive roller forre-routing the fiber.

The guiding means 26 allow to guide the fiber between the clampingmeans, the rerouting means and the cutting means, and towards thecompaction roller, and include for example a channel formed at theassembly interface of two plates. The fiber unwound from the reel 91 aassociated with the module is guided at the entrance of the guidingmeans 26 by a pulley 27 which is rotatably mounted between two flangesattached to the functional module. The support element also carries onits first lateral face a mandrel 43 a, motorized or not, to receive thereel, so that the reel is mobile in rotation about a rotation axis El.The fiber unwound from the reel is routed to pulley 27 of the module bymeans of a set of pulleys (not shown), rotatably mounted on the lateralface 40 a. A tension control system can also be provided in the fiberpath between the reel and pulley 27 to take up the slack and/or controlthe rotation of the mandrel.

Similarly, with reference to FIGS. 6, 8 and 10, the upstream functionalmodule 2 b is mounted so as to be movable in translation in directionT2, the upstream functional module being equipped with carriages 21mounted sliding on a rail 42 b attached to the support element. Themodule is assembled at its upper part to the end of the rod of acompaction cylinder 5 b, the cylinder being assembled by its body to thesupport element. The upstream functional module carries at its bottompart a compaction roller 3 b. The compaction roller 3 b is mountedbetween two flanges 22 b of the downstream functional module, movable inrotation about a rotation axis B2, which is perpendicular to thedirection T2. During the displacement of the module in translation indirection T2, the rotation axis B2 of the compaction roller 3 b of thismodule displaces in the same plane C as the rotation axis B1 of thecompaction roller 3 a of the downstream functional module.

The downstream functional module comprises fiber guiding means 26 forguiding the fiber entering the module towards the compaction rolleralong a plane P2, the planes P1 and P2 being arranged on the same sideof plane C, the plane P2 forming an angle α₂ with plane C which isgreater than the angle α₁, plane P1 being arranged upstream a plane P2with respect to the advancement direction of the head during lay-up. Thedownstream functional module includes cutting means 23, rerouting means24, and clamping means, the means being identical to those of thedownstream functional module.

The upstream functional module has a shape that is different from theone of the downstream functional module, so that the guiding plane P2 isoffset from the guiding plane P1. As shown in FIG. 11, the guidingmeans, cutting means, rerouting means and clamping means of the upstreamfunctional module are offset in relation to those of the downstreamfunctional module. In order to limit the cantilever, the rail 42 b onwhich the upstream functional module is mounted is offset in relation tothe rail 42 a on which the downstream functional module is mounted. Theupstream functional module also carries a pulley 27 rotatably mountedbetween two flanges, to guide the fiber unwound from reel 91 b at theentrance of the functional module.

The support element also carries on its first lateral face 40 a amandrel 43 b, motorized or not, to receive the reel 90 b, so that thereel is mobile in rotation about a rotation axis E2, as well as, aspreviously, a set of guiding pulleys and a possible tension controlsystem.

The four support elements are mounted on the frame so that the rotationaxis of the rollers are all arranged substantially in the same plane C.

The compaction rollers are all identical and are preferably able toconform to the application surface, especially to convex and/or concaveapplication surfaces. Each compaction roller is preferably a compactionroller made of a so-called flexible material, which is elasticallydeformable, such as an elastomer. The roller comprises a cylinder madeof flexible material, which is mounted fixed in rotation on a rigidaxis, e.g. made of metal, by which the roller is mounted free to rotatebetween two flanges.

Each compaction cylinder 5 a, 5 b is able to displace its associatedfunctional module between an extreme high position and an extreme lowposition. In FIG. 4, both modules are in extreme high position. In FIGS.7 and 8, the downstream functional module is in extreme low positionwhile the upstream functional module is in extreme high position.

For example, each compaction cylinder is a double-acting cylinder,preferably pneumatic, with two chambers supplied with compressed air, afirst lower chamber between the piston and the functional module and asecond upper chamber on the opposite side of the piston.

For the lay-up of a fiber with a functional module, the module iselastically urged to its extreme low position by its compactioncylinder. The head is brought into contact with the lay-up surface, withthe roller in contact with the lay-up surface. The compaction force forthe lay-up can be regulated by adapting the compressed air supplypressure in the upper chamber of the cylinder. During lay-up, thefunctional module can displace between its extreme low position and itsextreme high position to conform to the lay-up surface. When the moduleis not used to lay up a fiber, it is held in extreme high position bysupplying compressed air to the lower chamber.

As an example, in FIGS. 1 to 3, the four functional modules of the twosupport elements 4 a and 4 b are in extreme low position for the lay-upof a four-fiber band, while the other four functional modules of theother two support elements 4 c and 4 d are held in extreme highposition. During lay-up, the functional modules of the support elementsare able to displace between their extreme high and extreme lowpositions independently of each other, depending on variations ingeometry of the application surface.

The guiding means, as well as the cutting means, at least at theblade(s) of the cutting system, necessarily have a transverse dimensiongreater than the fiber width. To enable the lay-up of fiber bands inwhich the fibers are substantially edge to edge, the guiding means andthe cutting means of the upstream functional modules and those of thedownstream functional modules are arranged in such a way as to allow thedisplacement of the functional modules independently of each otherbetween their extreme low position and their extreme high position. Inthe case of a head intended for the lay-up of bands of edge-to-edgefiber, the head comprises compaction rollers with a width smaller thanthat of the fibers, the difference in width corresponding to the spacerequired for the mounting in rotation of the compaction rollers betweentwo flanges. The spacing between the lateral faces of two adjacentcompaction rollers basically corresponds to the thicknesses of the twoadjacent flanges plus an inter-flange clearance.

The head includes a heating system associated with each functionalmodule to heat at least the application surface upstream of thecompaction roller, preferably the application surface upstream of theroller, as well as the fiber to be laid up at the outlet of the guidingmeans. For the sake of clarity of the figures, the heating systems areshown only in FIGS. 12 to 14. Each support element 4 carries a heatingsystem 6 a associated with the downstream functional module 2 a and aheating system 6 b associated with the upstream functional module 2 b.The heating systems are mounted on the support element upstream of thefunctional modules in relation to the advancement direction of the head.

In the present embodiment, each heating system comprises a hot air torch61 a, 61 b, preferably electric, of compressed air type or associatedwith a turbine, able to emit a flow of hot air. Each torch is mounted ona support 62 mounted so as to be mobile in translation in direction T2,via carriages 63 attached to the support sliding on a rail 64 attachedto the support element. The heating system 6 a is connected to thedownstream functional module by a connecting arm 65 a, so that the hotair torch displaces in translation with the downstream functional moduleduring lay-up. Similarly, the heating system 6 b is connected to theupstream functional module 2 b by a connecting arm 65 b.

The mounting of the hot air torch is carried out in such a way that thehot air flow 66 is directed towards the nip area between the roller andthe application surface. The connection of the hot air torch to itsfunctional module guarantees optimal heating for the lay-up of thefiber.

The mounting of the heating systems on rails allows the cantilever ofthe functional modules to be limited. However, according to anembodiment, each heating system is mounted directly on a functionalmodule.

In an embodiment variant, the heating system comprises two air torchesfor each functional module, for example, one above the other.

The heating system can furthermore include one or more infrared lampsmounted on the support element upstream of the torch(s) to heat thelay-up surface.

In other embodiments, the above-mentioned air torch heating system isreplaced with a laser type heating system or a flash lamp type heatingsystem, as described in patent document WO2014/029969 or WO2017/134453.In the case of a laser or flash lamp type heating system, the radiationis directed obliquely towards the nip area or contact area between theapplication roller and the application surface, in order to heat thefiber located on the roller, before its compaction by the latter, aswell as the application surface and/or one or more previously appliedfibers.

The fibers are preferably tow-type continuous flat fibers preimpregnatedwith a thermosetting resin or a thermoplastic resin, or dry fibersprovided with a binder. The binder is in the form of powder and/or oneor more veils, preferably of the thermoplastic type.

The head according to an embodiment of the invention is particularlyadvantageous for lay-up of dry fibers provided with a binder or fiberspreimpregnated with thermoplastic resin.

The head can be adapted for the lay-up of fibers of different widths,but is particularly advantageous for the lay-up of fibers of at leasthalf an inch in width, for example one inch, one and a half inch, or twoinches. For a width of up to half an inch, the fibers can be wound intotraverse winding spools with helical turns. Beyond half an inch inwidth, the fiber is wound into spools or reels without traverse winding.

With reference to FIGS. 1 and 2, the support elements are arranged sideby side in a lay-up position, in which the head is able to lay up afiber band consisting of fibers arranged edge to edge, and in which thesupport elements are centered with respect to the axis A. The supportelements are equipped with assembly or locking means 44 a, 44 b, forexample pneumatic means, enabling two adjacent elements to be assembledand disassembled. The two outer support elements 4 a and 4 d are eachequipped with a motor 45, 46 whose shaft is equipped with a pinion 451meshing with a gear rack 47, 48 mounted on the support element to allowthe displacement of the functional modules 4 a, 4 b in translation inthe direction T1.

In the lay-up position of the support elements shown in FIGS. 1 and 2,the support elements are assembled to each other. The holding in thelay-up position is ensured by the motors 45, 46. As an alternative,locking means for locking in translation.

FIGS. 15 to 18 show the different positions of the support elements forcarrying out maintenance operations on the upstream and downstreamfunctional modules of the support elements, as well as for loading newfiber reels.

In the lay-up position, the first main face 40 a of the outer supportelement 4 a located on the side of the first end 14 is accessible, forexample to access its upstream functional module to carry outmaintenance operations on its cutting means, rerouting means and/orclamping means, on its compaction roller, to carry out a fiber reelchange, and to carry out the passage of fiber from the reel to thecompaction roller. The second main face 40 b of the external supportelement 4 d is also accessible to access its upstream functional moduleand its associated reel to carry out the above-mentioned operations.

Starting from this lay-up position, the outer support element 4 d isdisassembled from the adjacent support element 4 c, by controlling theirlocking means 44 a, 44 b, and its motor 46 is controlled to displace ittowards the second end 15, as shown in FIGS. 15 and 16. The motor 45 ofthe outer support element 4 a is controlled to displace it towards thefirst end 14, with the support element 4 e assembled to the supportelement 4 b, itself assembled to the motorized outer support element 4a.

In this maintenance position, the outer support element 4 d is displacedaway from the support element 4 c, so that an operator can access themain faces facing these support elements and carry out maintenanceoperations on the functional modules and reels that are accessible fromthese faces.

From this maintenance position in FIGS. 15 and 16, the motors 45, 46 canbe controlled to bring the support elements back to the lay-up positionof FIG. 1, then after assembly of support element 4 c to support element4 d, and disassembly of support element 4 c from support element 4 b,the motors are controlled to bring the outer support elements back tothe ends 14, 15 as shown in FIG. 17. In this maintenance position, anoperator can carry out maintenance operations on the functional modulesand associated reels accessible from the main faces facing the centralfunctional elements 4 c and 4 b.

The motors 45, 46 can then be controlled to bring the support elementsback to the lay-up position, then after assembly of support element 4 bto support element 4 c, and disassembly of support element 4 b fromsupport element 4 a, the motors are controlled to bring the outersupport elements back to the ends 14, 15 as shown in FIG. 18. In thismaintenance position, an operator can carry out maintenance operationson the functional modules and associated reel of the main faces facingthe functional elements 4 b and 4 a.

FIGS. 16, 17 and 18 illustrate the three maintenance positions of thesupport elements of the head that allow maintenance operations to becarried out on all functional modules and reels.

The use of two motors, in particular to return to the lay-up positionbetween each maintenance position, makes it possible to carry outchanges of position more quickly. Alternatively, the changeover from amaintenance position to the other is carried out using only one motor.In another embodiment, only one of the two support elements ismotorized, and is used to carry out the different maintenance positions.

The axial locking of the reel 91 a of the external support element 4 aon its mandrel, and the axial locking of the reel 91 b of the externalsupport element 4 d on its mandrel are ensured by specific locking meansequipping the mandrels. For the other reels of the support elements, theaxial locking is advantageously obtained thanks to the facing supportelement in the lay-up position, in particular thanks to the facingmandrels of the support elements.

Advantageously, one of the outer support elements 4 a or 4 d isconnected to an electrical source, the assembly of the support elementsto each other allows the electrical connection of the different supportelements to the source, for example for the power supply of heatingsystems.

FIGS. 19 and 20 show a head 101 according to a embodiment variant, whichdiffers from head 1 described above in that it additionally compriseslimiting means for limiting the relative strokes of two adjacentfunctional modules in compaction direction T2. Each functional module 2a, 2 b comprises on one of its lateral faces a protruding finger 28extending in the direction T1, and on its other lateral face a recessextending in the compaction direction and defining an upper stop 29 aand a lower stop 29 b. In the lay-up position, the finger of onefunctional module is positioned between the two stops of the recess ofan adjacent module, and its recess receives between its two stops thefinger of the other adjacent module. For the two externally locatedfunctional modules that are adjacent to only one other functionalmodule, one includes only a finger that is positioned in the recess ofthe adjacent module, and the other includes only its recess thatreceives the finger of its adjacent module. The distance between the twostops defines the maximum relative stroke between two adjacentfunctional modules.

As an example, as shown in FIG. 20, when the functional modulereferenced 2 a is urged towards its lower position to lay up a singlefiber by means of this functional module, the functional modules on itsright in FIG. 20 are also mechanically driven by their fingers restingagainst the corresponding upper stops, and the functional modules on itsleft are mechanically driven by their lower stops resting againstresting against the corresponding fingers.

Although the invention has been described in connection with aparticular embodiment, it is obvious that it is by no means limited tothat embodiment and that it comprises all the technical equivalents ofthe means described as well as their combinations if they fall withinthe scope of the invention.

1. A fiber application head for the production of composite materialparts by application of bands formed of several continuous fibersarranged side by side, comprising a compaction system comprising severalindependent compaction rollers and compaction cylinders, and for eachfiber, cutting means and rerouting means, comprising: for each fiber,the head comprises a functional module including the cutting means andthe rerouting means, each functional module is mounted so as to bemovable in translation along a compaction direction on a support elementof the head, each compaction roller is mounted on one or more adjacentfunctional modules, a compaction cylinder is associated with thefunctional module(s) associated with a compaction roller for thedisplacement in translation of the functional module(s), said headfurther comprising heating means comprising an independent heatingsystem associated with each compaction roller, said heating system beingable to displace together with the functional module(s) associated withsaid compaction roller.
 2. The application head according to claim 1,wherein the heating system is able to emit thermal radiation towards thenip area between the compaction roller and the application surface, inorder to heat each fiber located on the compaction roller, before itscompaction by the latter, as well as the application surface and/or oneor more previously applied fibers.
 3. The application head according toclaim 1, wherein each heating system comprises one or more hot airtorches, a laser type heating system, or a flash lamp type heatingsystem.
 4. The application head according to claim 1, wherein eachheating system is mounted so as to be movable in translation in thecompaction direction on the support element and is mechanicallyconnected by at least one rigid arm to said functional module(s).
 5. Theapplication head according to claim 1, wherein each heating system ispivotally mounted on the support element and is mechanically connectedby at least one connecting rod to said functional module(s).
 6. Theapplication head according to claim 1, wherein it comprises onecompaction roller per functional module.
 7. The method for themanufacture of a composite material part comprising the application ofcontinuous fibers onto an application surface, wherein the applicationof fibers is carried out by means of a fiber application head accordingto claim 1, by relative displacement of the application head withrespect to the lay-up surface along lay-up trajectories.